The trials, funded by grants of $16 million and $7.9 million respectively, are part of a national Alzheimer's plan, a sweeping effort to find an effective way to prevent or treat Alzheimer's by 2025 and improve the care of those already afflicted with the brain-wasting disease.

Experts predict that without more effective drugs, the number of Americans with Alzheimer's will double by 2050 and annual related healthcare costs could soar to more than $1 trillion.

The fatal form of dementia affects about 5.1 million Americans today and current treatments address symptoms, but cannot prevent the disease or stop its progression.

Details of the two clinical trials are due to be announced by the National Institutes of Health at a national meeting on Alzheimer's research in Bethesda, Maryland, later on Tuesday.

One of the studies will involve the use of a drug that attacks amyloid -- a protein thought to be a cause of Alzheimer's -- in an international study of people who are genetically predisposed to develop the disease early.

The second will test the use of an insulin nasal spray to restore memory in patients with Alzheimer's.

An earlier small study of the latter approach by the University of Washington published last year showed memory improvements in people with mild to moderate Alzheimer's or a pre-Alzheimer's condition called amnestic mild cognitive impairment.

FUNDING

Funding for the new initiatives will come from $50 million the Obama administration has set aside for the national Alzheimer's plan for fiscal 2012.

Another $100 million has been earmarked for fiscal 2013, including $80 million for research, $4.2 million for public awareness, $4 million for provider education, $10.5 million in caregiver support, and $1.3 million to improve data collection.

The national plan, called for in the National Alzheimer's Project Act signed by President Barack Obama last year, and drafted by the Department of Health and Human Services (HHS), reflects the input of 3,600 people or organizations.

It includes development of new training for doctors, a public education campaign, including TV advertisements and a website -- www.alzheimers.gov -- to help families and carers find services and support.

"These actions are the cornerstones of an historic effort to fight Alzheimer's disease," HHS Secretary Kathleen Sebelius said in a statement.

"This is a national plan — not a federal one, because reducing the burden of Alzheimer's will require the active engagement of both the public and private sectors."

The 2025 goal has been the subject of lengthy debate in the advisory council tasked with helping to write the national plan.

"We had people saying it was overly ambitious and we had people who said it wasn't ambitious enough," said Don Moulds, principal deputy assistant secretary for planning and evaluation at HHS, in a telephone interview.

Moulds said there was concern that an earlier goal might skew research funding into treatments that might be easy hits, but not game-changing treatments. In the end, the 2025 target was the earliest date a significant treatment could be found.

Although work was already going on to find a treatment for Alzheimer's, Moulds said the national plan and its specific targets and timelines would help focus the government's efforts.

"It's a huge initiative and a very ambitious step in the right direction," he said.

(Reporting by Julie Steenhuysen; Editing by David Brunnstrom)

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